3seg mode, 2 lseg mode – Micromod Micro-DCI: 53SL6000 Single Loop Controller User Manual

Page 52

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Table 6-1. Characterizer Parameters

(ProG Menu

chr Module)

Prompt

Description

Dft

K01 -

K26

Assignments for K01 through K26 for
the three segment (3SEG)
characterizer, linear segment (LSEG)
characterizer, the setpoint
programmer (PGrM), and the digital-
to-analog converter (DtoA) are as
follows

3SEG (executes 5 third order
polynomials):
K01 - K06: Six endpoints that
partition the 5
segments.
K07 - K10: Segment 1 (equation 1)
coefficients.
K11 - K14: Segment 2 (equation 2)
coefficients.
K15 - K18: Segment 3 (equation 3)
coefficients.
K19 - K22: Segment 4 (equation 4)
coefficients.
K23 - K26: Segment 5 (equation 5)
coefficients.

LSEG (13 ordered pairs for 12
segments. Each input value must
be greater than the previous one):
K01 - K13: input coordinates.
K14 - K26: output coordinates.
Ordered segment pairs are K01, K14;
K02, K15; etc.

PGrM:
K01 - K13:
Entered time intervals in
whole seconds. Negative
numbers not permitted.
K14 - K26: Target analog output from
characterizer (per step).

DtoA:
K1:
B input ramp rate (up).
K2: C input ramp rate (down).
K3: Lower output limit.
K4: Upper output limit.

0.0

6.2.1. 3SEG Mode

The third order polynomial segment characterizer
allows the user to define five adjacent segments.
Each segment has an independent third order poly-
nomial defining the relationship between the A in-
put value and the analog output value. Whenever
the A input value does not fall within any of the five
segments, a logical 1 value is produced at the char-
acterizer’s digital output; otherwise, a logical 0
value is present at the digital output. The charac-
terizer analog output value is forced to reflect the
value related to the nearest defined segment when-
ever the A input is outside all defined segments.

The five segments are defined by the constants K1
through K6. The values assigned to these con-
stants must be monotonically increasing, going
from K1 to K6, to ensure the segments are adja-
cent. Constants K7 through K26 are divided into
five groups, each with four constants. The group
acts as a set of coefficients for an individual seg-
ment’s polynomial as given by the equation and
table below:

Output

=

WA

3

+

XA

2

+

YA

+

Z

Equation Segment

W

X

Y

Z

1

K1-K2

K7

K8

K9

K10

2

K2-K3

K11

K12

K13

K14

3

K3-K4

K15

K16

K17

K18

4

K4-K5

K19

K20

K21

K22

5

K5-K6

K23

K24

K25

K26

This characterizer mode provides the capability to
linearize complex curves (e.g., thermocouple
curves). A linearization example of an E-type ther-
mocouple (operating range -115

°

to 1000

°

C) with

the characterizer A input provided in millivolts is as
follows:

Eq.

Segment

W

X

Y

Z

1

K1: -5.90
K2: 0.0

K7:
0.03947

K8:
0.1575

K9:
17.20

K10:
0.04199

2

K2: 0.0
K3: 13.42

K11:
0.004269

K12:
0.2143

K13:
17.01

K14:
0.02144

3

K3: 7.0
K4: 36.99

K15:
0.0007227

K16:
0.0769

K17:
15.12

K18:
9.264

4

K4: 36.99
K5: 61.02

K19:
0.0002274

K20:
0.02488

K21:
13.26

K22:
32.13

5

K5: 61.02
K6: 76.40

K23:
0.0001247

K24:
0.004976

K25:
11.95

K26:
60.8

Note: many of the values shown in this example
can not be entered directly at the front display
panel due to the limited size of the data entry dis-
play; however, the values given are easily loadable
via the communications network datalink interface
(requires the RS-485 option module).

6.2.2 LSEG Mode

The linear segment characterizer allows the user to
define a relationship between the A input and the
analog output value via a piecewise linear approxi-
mation. The approximation is made up of twelve
adjacent line segments. Each line segment end-
points are defined by two pairs of coordinates, re-
quir ing thirteen coor dinate pairs in all. The
coordinate values are stored in characterizer con-
stants K1-K26.

Micro-DCI

53SL6000 Controller

6-2

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